Good monsoon may save Delhi from being fogged out this year

After two years of dense, record-breaking fog, flyers at the Delhi airport can breathe it easy this winter.

According to the met department, the winter of 2010-2011 might not witness the extreme dense fog it saw in the last two winters, thanks to the excessive rainfall received by the city this monsoon.

Though December 2009 didn't see much fog-related disruptions at the Indira Gandhi International Airport, January 2010 more than made up for that and took the tally of dense fog hours to 174, with continuous fog for days. More than 2,000 flights were delayed and 137 had to be diverted in January alone.

In the last decade, the winter of 2002-2003 saw the worst fog, with 190 hours of CAT III dense fog (visibility below 200 metres).

While last winter saw 174 hours of dense fog, the winter of 2008-2009 too neared the record, with 167 hours of zero visibility at the airport.

"We are expecting a normal dense fog period this winter with around 100-120 hours of dense fog," said RK Jenamani, director-in-charge of the IGIA met unit.

"Last winter saw not just huge hours of dense fog, the problem period was unevenly distributed and there was dense fog for days during January," he said.

"We have seen that usually when Delhi receives abundant rainfall during the monsoon, there is less extreme fog in the winter," he said.

"Last year, there was not much monsoon rainfall and the fog was one of the worst of the decade."

IGIA is one of the worst fog-affected airports in the world and has witnessed unusual fog conditions in the last three years. While there was record setting fog in the winters of 2008-2009 and 2009-2010, there was only 10 hours of fog between December 2007 and February 2008.

"The conditions required for the formation of fog have yet not appeared in the atmosphere and there could be just a couple of days of fog over the next month," he said.

"Humidity is required for fog to set in but too much rainfall doesn't let fog form," Jenamani added.